Organic light emitting diode (OLED) displays are becoming more commonplace for their numerous advantages. However, emissive display technologies, such as OLED displays, suffer from differential aging (or luminance degradation), and must be carefully analyzed and used to ensure that lifetime expectations are met. Differential aging is where portions or colors of the display used more frequently emit a lower luminance than portions used less frequently. Light valve technology such as liquid crystal, interferometric modulator, LCOS, micro-minor, and electrophoretic displays do not suffer from differential aging because they depend on a general light source that decays independent of localized screen use. Since emissive technology displays suffer from differential aging, screen saver functions are required if the same data is displayed over long periods of time. Although OLED displays have many benefits, their major disadvantage is aging. In addition, aging of OLED displays is accelerated substantially at elevated temperatures, commonly associated with automotive environments.
For example, an implementer of a display may configure or request OLEDs to be driven at levels greater than 600 cd/m2 in order to maintain display visibility, the amount of permanent luminance consumption (or amount that the luminance decreases) increases dramatically as the OLED operating temperature is increased. The amount of compensation that may be applied at the pixel level to minimize burned-in image effects is limited which necessitates the use other methods to minimize the OLED consumption rate under infrequent adverse conditions.
Another technique has been proposed, thermal derating, to address the problems associated with differential aging. A thermal derating method allows for control of an overall temperature associated with a display technologies operation, in order to maximize the lifetime of an OLED.
However, each of the above proposed methods may not be robust enough to handle the issues associated with luminance degradation.